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      1 /******************************************************************************
      2  *
      3  *  Copyright (C) 1999-2012 Broadcom Corporation
      4  *
      5  *  Licensed under the Apache License, Version 2.0 (the "License");
      6  *  you may not use this file except in compliance with the License.
      7  *  You may obtain a copy of the License at:
      8  *
      9  *  http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  *  Unless required by applicable law or agreed to in writing, software
     12  *  distributed under the License is distributed on an "AS IS" BASIS,
     13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  *  See the License for the specific language governing permissions and
     15  *  limitations under the License.
     16  *
     17  ******************************************************************************/
     18 
     19 /*****************************************************************************
     20  *
     21  *  This file contains collection of utility functions used the RFCOMM unit
     22  *
     23  *****************************************************************************/
     24 
     25 #include "bt_target.h"
     26 #include "bt_common.h"
     27 
     28 #include "btm_api.h"
     29 #include "btm_int.h"
     30 #include "rfcdefs.h"
     31 #include "port_api.h"
     32 #include "port_ext.h"
     33 #include "port_int.h"
     34 #include "rfc_int.h"
     35 #include "btu.h"
     36 #include "bt_utils.h"
     37 
     38 #include <string.h>
     39 
     40 extern fixed_queue_t *btu_general_alarm_queue;
     41 
     42 /*******************************************************************************
     43 **
     44 ** Function         rfc_calc_fcs
     45 **
     46 ** Description      Reversed CRC Table , 8-bit, poly=0x07
     47 **                  (GSM 07.10 TS 101 369 V6.3.0)
     48 *******************************************************************************/
     49 static const UINT8 rfc_crctable[] =
     50 {
     51     0x00, 0x91, 0xE3, 0x72, 0x07, 0x96, 0xE4, 0x75,  0x0E, 0x9F, 0xED, 0x7C, 0x09, 0x98, 0xEA, 0x7B,
     52     0x1C, 0x8D, 0xFF, 0x6E, 0x1B, 0x8A, 0xF8, 0x69,  0x12, 0x83, 0xF1, 0x60, 0x15, 0x84, 0xF6, 0x67,
     53     0x38, 0xA9, 0xDB, 0x4A, 0x3F, 0xAE, 0xDC, 0x4D,  0x36, 0xA7, 0xD5, 0x44, 0x31, 0xA0, 0xD2, 0x43,
     54     0x24, 0xB5, 0xC7, 0x56, 0x23, 0xB2, 0xC0, 0x51,  0x2A, 0xBB, 0xC9, 0x58, 0x2D, 0xBC, 0xCE, 0x5F,
     55 
     56     0x70, 0xE1, 0x93, 0x02, 0x77, 0xE6, 0x94, 0x05,  0x7E, 0xEF, 0x9D, 0x0C, 0x79, 0xE8, 0x9A, 0x0B,
     57     0x6C, 0xFD, 0x8F, 0x1E, 0x6B, 0xFA, 0x88, 0x19,  0x62, 0xF3, 0x81, 0x10, 0x65, 0xF4, 0x86, 0x17,
     58     0x48, 0xD9, 0xAB, 0x3A, 0x4F, 0xDE, 0xAC, 0x3D,  0x46, 0xD7, 0xA5, 0x34, 0x41, 0xD0, 0xA2, 0x33,
     59     0x54, 0xC5, 0xB7, 0x26, 0x53, 0xC2, 0xB0, 0x21,  0x5A, 0xCB, 0xB9, 0x28, 0x5D, 0xCC, 0xBE, 0x2F,
     60 
     61     0xE0, 0x71, 0x03, 0x92, 0xE7, 0x76, 0x04, 0x95,  0xEE, 0x7F, 0x0D, 0x9C, 0xE9, 0x78, 0x0A, 0x9B,
     62     0xFC, 0x6D, 0x1F, 0x8E, 0xFB, 0x6A, 0x18, 0x89,  0xF2, 0x63, 0x11, 0x80, 0xF5, 0x64, 0x16, 0x87,
     63     0xD8, 0x49, 0x3B, 0xAA, 0xDF, 0x4E, 0x3C, 0xAD,  0xD6, 0x47, 0x35, 0xA4, 0xD1, 0x40, 0x32, 0xA3,
     64     0xC4, 0x55, 0x27, 0xB6, 0xC3, 0x52, 0x20, 0xB1,  0xCA, 0x5B, 0x29, 0xB8, 0xCD, 0x5C, 0x2E, 0xBF,
     65 
     66     0x90, 0x01, 0x73, 0xE2, 0x97, 0x06, 0x74, 0xE5,  0x9E, 0x0F, 0x7D, 0xEC, 0x99, 0x08, 0x7A, 0xEB,
     67     0x8C, 0x1D, 0x6F, 0xFE, 0x8B, 0x1A, 0x68, 0xF9,  0x82, 0x13, 0x61, 0xF0, 0x85, 0x14, 0x66, 0xF7,
     68     0xA8, 0x39, 0x4B, 0xDA, 0xAF, 0x3E, 0x4C, 0xDD,  0xA6, 0x37, 0x45, 0xD4, 0xA1, 0x30, 0x42, 0xD3,
     69     0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1,  0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF
     70 };
     71 
     72 
     73 /*******************************************************************************
     74 **
     75 ** Function         rfc_calc_fcs
     76 **
     77 ** Description      This function calculate FCS for the RFCOMM frame
     78 **                  (GSM 07.10 TS 101 369 V6.3.0)
     79 **
     80 ** Input            len - number of bytes in the message
     81 **                  p   - points to message
     82 **
     83 *******************************************************************************/
     84 UINT8 rfc_calc_fcs (UINT16 len, UINT8 *p)
     85 {
     86     UINT8  fcs = 0xFF;
     87 
     88     while (len--)
     89     {
     90         fcs = rfc_crctable[fcs ^ *p++];
     91     }
     92 
     93     /* Ones compliment */
     94     return (0xFF - fcs);
     95 }
     96 
     97 
     98 /*******************************************************************************
     99 **
    100 ** Function         rfc_check_fcs
    101 **
    102 ** Description      This function checks FCS for the RFCOMM frame
    103 **                  (GSM 07.10 TS 101 369 V6.3.0)
    104 **
    105 ** Input            len          - number of bytes in the message
    106 **                  p            - points to message
    107 **                  received_fcs - received FCS
    108 **
    109 *******************************************************************************/
    110 BOOLEAN rfc_check_fcs (UINT16 len, UINT8 *p, UINT8 received_fcs)
    111 {
    112     UINT8  fcs = 0xFF;
    113 
    114     while (len--)
    115     {
    116         fcs = rfc_crctable[fcs ^ *p++];
    117     }
    118 
    119     /* Ones compliment */
    120     fcs = rfc_crctable[fcs ^ received_fcs];
    121 
    122     /*0xCF is the reversed order of 11110011.*/
    123     return (fcs == 0xCF);
    124 }
    125 
    126 
    127 /*******************************************************************************
    128 **
    129 ** Function         rfc_alloc_multiplexer_channel
    130 **
    131 ** Description      This function returns existing or new control block for
    132 **                  the BD_ADDR.
    133 **
    134 *******************************************************************************/
    135 tRFC_MCB *rfc_alloc_multiplexer_channel (BD_ADDR bd_addr, BOOLEAN is_initiator)
    136 {
    137     int i, j;
    138     tRFC_MCB *p_mcb = NULL;
    139     RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel: bd_addr:%02x:%02x:%02x:%02x:%02x:%02x",
    140                                 bd_addr[0], bd_addr[1], bd_addr[2], bd_addr[3], bd_addr[4], bd_addr[5]);
    141     RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d", is_initiator);
    142 
    143     for (i = 0; i < MAX_BD_CONNECTIONS; i++)
    144     {
    145         RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel rfc_cb.port.rfc_mcb[%d].state:%d",
    146                             i, rfc_cb.port.rfc_mcb[i].state);
    147         RFCOMM_TRACE_DEBUG("(rfc_cb.port.rfc_mcb[i].bd_addr:%02x:%02x:%02x:%02x:%02x:%02x",
    148                                 rfc_cb.port.rfc_mcb[i].bd_addr[0], rfc_cb.port.rfc_mcb[i].bd_addr[1],
    149                                 rfc_cb.port.rfc_mcb[i].bd_addr[2], rfc_cb.port.rfc_mcb[i].bd_addr[3],
    150                                 rfc_cb.port.rfc_mcb[i].bd_addr[4], rfc_cb.port.rfc_mcb[i].bd_addr[5]);
    151 
    152         if ((rfc_cb.port.rfc_mcb[i].state != RFC_MX_STATE_IDLE)
    153          && (!memcmp (rfc_cb.port.rfc_mcb[i].bd_addr, bd_addr, BD_ADDR_LEN)))
    154         {
    155             /* Multiplexer channel found do not change anything */
    156             /* If there was an inactivity timer running stop it now */
    157             if (rfc_cb.port.rfc_mcb[i].state == RFC_MX_STATE_CONNECTED)
    158                 rfc_timer_stop (&rfc_cb.port.rfc_mcb[i]);
    159             RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d, found, state:%d, p_mcb:%p",
    160                                 is_initiator, rfc_cb.port.rfc_mcb[i].state, &rfc_cb.port.rfc_mcb[i]);
    161             return (&rfc_cb.port.rfc_mcb[i]);
    162         }
    163     }
    164 
    165     /* connection with bd_addr does not exist */
    166     for (i = 0, j = rfc_cb.rfc.last_mux + 1; i < MAX_BD_CONNECTIONS; i++, j++)
    167     {
    168         if (j >= MAX_BD_CONNECTIONS)
    169             j = 0;
    170 
    171         p_mcb = &rfc_cb.port.rfc_mcb[j];
    172         if (rfc_cb.port.rfc_mcb[j].state == RFC_MX_STATE_IDLE)
    173         {
    174             /* New multiplexer control block */
    175             alarm_free(p_mcb->mcb_timer);
    176             fixed_queue_free(p_mcb->cmd_q, NULL);
    177             memset (p_mcb, 0, sizeof (tRFC_MCB));
    178             memcpy (p_mcb->bd_addr, bd_addr, BD_ADDR_LEN);
    179             RFCOMM_TRACE_DEBUG("rfc_alloc_multiplexer_channel:is_initiator:%d, create new p_mcb:%p, index:%d",
    180                                 is_initiator, &rfc_cb.port.rfc_mcb[j], j);
    181 
    182             p_mcb->mcb_timer = alarm_new("rfcomm_mcb.mcb_timer");
    183             p_mcb->cmd_q = fixed_queue_new(SIZE_MAX);
    184 
    185             p_mcb->is_initiator = is_initiator;
    186 
    187             rfc_timer_start (p_mcb, RFC_MCB_INIT_INACT_TIMER);
    188 
    189             rfc_cb.rfc.last_mux = (UINT8) j;
    190             return (p_mcb);
    191         }
    192     }
    193     return (NULL);
    194 }
    195 
    196 
    197 /*******************************************************************************
    198 **
    199 ** Function         rfc_release_multiplexer_channel
    200 **
    201 ** Description      Release a multiplexer control block
    202 **
    203 *******************************************************************************/
    204 void rfc_release_multiplexer_channel (tRFC_MCB *p_mcb)
    205 {
    206     /* Remove the MCB from the mapping table */
    207     rfc_save_lcid_mcb(NULL, p_mcb->lcid);
    208 
    209     /* Remove the MCB from the ports */
    210     for (int i = 0; i < MAX_RFC_PORTS; i++) {
    211         if (rfc_cb.port.port[i].rfc.p_mcb == p_mcb)
    212             rfc_cb.port.port[i].rfc.p_mcb = NULL;
    213     }
    214 
    215     rfc_timer_stop (p_mcb);
    216     alarm_free(p_mcb->mcb_timer);
    217 
    218     fixed_queue_free(p_mcb->cmd_q, osi_free);
    219 
    220     memset (p_mcb, 0, sizeof (tRFC_MCB));
    221     p_mcb->state = RFC_MX_STATE_IDLE;
    222 }
    223 
    224 
    225 /*******************************************************************************
    226 **
    227 ** Function         rfc_timer_start
    228 **
    229 ** Description      Start RFC Timer
    230 **
    231 *******************************************************************************/
    232 void rfc_timer_start(tRFC_MCB *p_mcb, UINT16 timeout)
    233 {
    234     RFCOMM_TRACE_EVENT ("%s - timeout:%d seconds", __func__, timeout);
    235 
    236     period_ms_t interval_ms = timeout * 1000;
    237     alarm_set_on_queue(p_mcb->mcb_timer, interval_ms,
    238                        rfcomm_mcb_timer_timeout, p_mcb,
    239                        btu_general_alarm_queue);
    240 }
    241 
    242 
    243 /*******************************************************************************
    244 **
    245 ** Function         rfc_timer_stop
    246 **
    247 ** Description      Stop RFC Timer
    248 **
    249 *******************************************************************************/
    250 void rfc_timer_stop(tRFC_MCB *p_mcb)
    251 {
    252     RFCOMM_TRACE_EVENT("%s", __func__);
    253 
    254     alarm_cancel(p_mcb->mcb_timer);
    255 }
    256 
    257 
    258 /*******************************************************************************
    259 **
    260 ** Function         rfc_port_timer_start
    261 **
    262 ** Description      Start RFC Timer
    263 **
    264 *******************************************************************************/
    265 void rfc_port_timer_start(tPORT *p_port, UINT16 timeout)
    266 {
    267     RFCOMM_TRACE_EVENT("%s - timeout:%d seconds", __func__, timeout);
    268 
    269     period_ms_t interval_ms = timeout * 1000;
    270     alarm_set_on_queue(p_port->rfc.port_timer, interval_ms,
    271                        rfcomm_port_timer_timeout, p_port,
    272                        btu_general_alarm_queue);
    273 }
    274 
    275 /*******************************************************************************
    276 **
    277 ** Function         rfc_port_timer_stop
    278 **
    279 ** Description      Stop RFC Timer
    280 **
    281 *******************************************************************************/
    282 void rfc_port_timer_stop(tPORT *p_port)
    283 {
    284     RFCOMM_TRACE_EVENT ("%s", __func__);
    285 
    286     alarm_cancel(p_port->rfc.port_timer);
    287 }
    288 
    289 
    290 /*******************************************************************************
    291 **
    292 ** Function         rfc_check_mcb_active
    293 **
    294 ** Description      Check if there are any opened ports on the MCB if not
    295 **                  start MCB Inact timer.
    296 **
    297 ** Returns          void
    298 **
    299 *******************************************************************************/
    300 void rfc_check_mcb_active (tRFC_MCB *p_mcb)
    301 {
    302     UINT16 i;
    303 
    304     for (i = 0; i < RFCOMM_MAX_DLCI; i++)
    305     {
    306         if (p_mcb->port_inx[i] != 0)
    307         {
    308             p_mcb->is_disc_initiator = FALSE;
    309             return;
    310         }
    311     }
    312     /* The last port was DISCed.  On the client side start disconnecting Mx */
    313     /* On the server side start inactivity timer */
    314     if (p_mcb->is_disc_initiator)
    315     {
    316         p_mcb->is_disc_initiator = FALSE;
    317         rfc_mx_sm_execute (p_mcb, RFC_MX_EVENT_CLOSE_REQ, NULL);
    318     }
    319     else
    320         rfc_timer_start (p_mcb, RFC_MCB_RELEASE_INACT_TIMER);
    321 }
    322 
    323 void rfcomm_port_timer_timeout(void *data)
    324 {
    325     tPORT *p_port = (tPORT *)data;
    326 
    327     rfc_port_sm_execute(p_port, RFC_EVENT_TIMEOUT, NULL);
    328 }
    329 
    330 void rfcomm_mcb_timer_timeout(void *data)
    331 {
    332     tRFC_MCB *p_mcb = (tRFC_MCB *)data;
    333 
    334     rfc_mx_sm_execute(p_mcb, RFC_EVENT_TIMEOUT, NULL);
    335 }
    336 
    337 /*******************************************************************************
    338 **
    339 ** Function         rfc_sec_check_complete
    340 **
    341 ** Description      The function called when Security Manager finishes
    342 **                  verification of the service side connection
    343 **
    344 ** Returns          void
    345 **
    346 *******************************************************************************/
    347 void rfc_sec_check_complete (BD_ADDR bd_addr, tBT_TRANSPORT transport, void *p_ref_data, UINT8 res)
    348 {
    349     tPORT *p_port = (tPORT *)p_ref_data;
    350     UNUSED(bd_addr);
    351     UNUSED(transport);
    352 
    353     /* Verify that PORT is still waiting for Security to complete */
    354     if (!p_port->in_use
    355      || ((p_port->rfc.state != RFC_STATE_ORIG_WAIT_SEC_CHECK)
    356       && (p_port->rfc.state != RFC_STATE_TERM_WAIT_SEC_CHECK)))
    357         return;
    358 
    359     rfc_port_sm_execute ((tPORT *)p_ref_data, RFC_EVENT_SEC_COMPLETE, &res);
    360 }
    361 
    362 
    363 /*******************************************************************************
    364 **
    365 ** Function         rfc_port_closed
    366 **
    367 ** Description      The function is called when port is released based on the
    368 **                  event received from the lower layer, typically L2CAP
    369 **                  connection down, DISC, or DM frame.
    370 **
    371 ** Returns          void
    372 **
    373 *******************************************************************************/
    374 void rfc_port_closed (tPORT *p_port)
    375 {
    376     tRFC_MCB *p_mcb = p_port->rfc.p_mcb;
    377 
    378     RFCOMM_TRACE_DEBUG ("rfc_port_closed");
    379 
    380     rfc_port_timer_stop (p_port);
    381 
    382     p_port->rfc.state = RFC_STATE_CLOSED;
    383 
    384     /* If multiplexer channel was up mark it as down */
    385     if (p_mcb)
    386     {
    387         p_mcb->port_inx[p_port->dlci] = 0;
    388 
    389         /* If there are no more ports opened on this MCB release it */
    390         rfc_check_mcb_active (p_mcb);
    391     }
    392 
    393     /* Notify port that RFC connection is gone */
    394     port_rfc_closed (p_port, PORT_CLOSED);
    395 }
    396 
    397 /*******************************************************************************
    398 **
    399 ** Function         rfc_inc_credit
    400 **
    401 ** Description      The function is called when a credit is received in a UIH
    402 **                  frame.  It increments the TX credit count, and if data
    403 **                  flow had halted, it restarts it.
    404 **
    405 ** Returns          void
    406 **
    407 *******************************************************************************/
    408 void rfc_inc_credit (tPORT *p_port, UINT8 credit)
    409 {
    410     if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT)
    411     {
    412         p_port->credit_tx += credit;
    413 
    414         RFCOMM_TRACE_EVENT ("rfc_inc_credit:%d", p_port->credit_tx);
    415 
    416         if (p_port->tx.peer_fc == TRUE)
    417             PORT_FlowInd(p_port->rfc.p_mcb, p_port->dlci, TRUE);
    418     }
    419 }
    420 
    421 /*******************************************************************************
    422 **
    423 ** Function         rfc_dec_credit
    424 **
    425 ** Description      The function is called when a UIH frame of user data is
    426 **                  sent.  It decrements the credit count.  If credit count
    427 **                  Reaches zero, peer_fc is set.
    428 **
    429 ** Returns          void
    430 **
    431 *******************************************************************************/
    432 void rfc_dec_credit (tPORT *p_port)
    433 {
    434     if (p_port->rfc.p_mcb->flow == PORT_FC_CREDIT)
    435     {
    436         if (p_port->credit_tx > 0)
    437             p_port->credit_tx--;
    438 
    439         if (p_port->credit_tx == 0)
    440             p_port->tx.peer_fc = TRUE;
    441     }
    442 }
    443 
    444 
    445 /*******************************************************************************
    446 **
    447 ** Function         rfc_check_send_cmd
    448 **
    449 ** Description      This function is called to send an RFCOMM command message
    450 **                  or to handle the RFCOMM command message queue.
    451 **
    452 ** Returns          void
    453 **
    454 *******************************************************************************/
    455 void rfc_check_send_cmd(tRFC_MCB *p_mcb, BT_HDR *p_buf)
    456 {
    457     /* if passed a buffer queue it */
    458     if (p_buf != NULL) {
    459         if (p_mcb->cmd_q == NULL) {
    460             RFCOMM_TRACE_ERROR("%s: empty queue: p_mcb = %p p_mcb->lcid = %u cached p_mcb = %p",
    461                                __func__, p_mcb, p_mcb->lcid,
    462                                rfc_find_lcid_mcb(p_mcb->lcid));
    463         }
    464         fixed_queue_enqueue(p_mcb->cmd_q, p_buf);
    465     }
    466 
    467     /* handle queue if L2CAP not congested */
    468     while (p_mcb->l2cap_congested == FALSE) {
    469         BT_HDR *p = (BT_HDR *)fixed_queue_try_dequeue(p_mcb->cmd_q);
    470         if (p == NULL)
    471             break;
    472         L2CA_DataWrite(p_mcb->lcid, p);
    473     }
    474 }
    475